You Gotta Know These Space Missions

Apollo 11 saw the first Moon landing and moonwalk by astronauts Neil Armstrong and Buzz Aldrin (astronaut Michael Collins piloted the Command Module in lunar orbit and never walked on the moon).

After the Lunar Module landed in the Sea of Tranquility, Armstrong said, “Houston, Tranquility Base here. The Eagle has landed.” Later stepping onto the lunar surface, he said, “That’s one small step for [a] man, one giant leap for mankind.” According to Chris Kraft, NASA officials chose Armstrong as the first to walk on the Moon because he was more humble than Aldrin, and because he was the Commander. However, the stated reason was that Armstrong’s seat was closer to the door. Apollo 11, like other Apollo missions, launched atop a Saturn V booster.

Vostok 1 and Vostok 6 transported the first human and the first woman into space (respectively, Yuri Gagarin and Valentina Tereshkova). Gagarin’s April 12, 1961 flight is still celebrated as Yuri’s Night. During Vostok 1, Gagarin completed a single orbit around Earth before re-entering and parachuting out of his capsule.

Vostok 6 was largely uneventful, though Tereshkova did note minor physical pains and also could not reach the scientific experiments aboard. Both Vostok 1 and 6 used Vostok-K boosters.

The launch of Sputnik 1, the first artificial satellite, by the USSR kicked off the so-called “Space Race.” The Space Race was manifestation of the Cold War where successes in launching objects and people into space was seen as a proxy for capacity to build intercontinental ballistic missiles. Sputnik 1 was originally intended to carry many scientific instruments, but those instruments were descoped, in favor of a simple radio transmitter. That transmitter broadcasted a “beep” at a specified interval, allowing scientists to map its deceleration as a result of atmospheric drag.

Sputnik 1 was followed by Sputnik 2, which carried a dog named Laika (meaning “barker”) into low-earth orbit, and was destroyed upon re-entry.

Voskhod 1 and Voskhod 2 were the only two missions of the Voskhod program, and were superseded quickly by the Soyuz program. The spacecrafts made use of Sergei Korolev’s designs. Korolev himself was preoccupied with the Moon race, again in a position of favor after the fall of Khrushchev (though Korolev died before the designs were used).

Voskhod 1 was the first flight to contain multiple astronauts, and Voskhod 2 was the platform for the first EVA (extra-vehicular activity or “spacewalk”). Alexey Leonov, who conducted the spacewalk on Voskhod 2, also participated in the later Apollo-Soyuz Test Project.

Apollo 13 was supposed to land in the Fra Mauro region of the Moon. An improperly-refurbished No. 2 oxygen tank and subsequent improper repairs caused the tank to rupture during a routine “cryo-stir” before entering lunar orbit. The explosion also damaged the No. 1 oxygen tank and caused further leakage. To bring back the astronauts, the orbiter was put on a free-return trajectory around the Moon. NASA engineers also solved power-management, water-conservation, and trajectory planning problems with the help of Ken Mattingly, the primary Command Module pilot who had been grounded due to exposure to German measles. All three astronauts returned to Earth safely, and the landing site was re-assigned to the subsequent Apollo 14 mission.

Apollo 1 was intended to be a test of the Command/Service Module in low-Earth orbit (LEO). However, a fire on the launchpad during a test killed the three astronauts aboard (Virgil “Gus” Grissom, Roger Chaffee, and Ed White). The fire was exacerbated by the pure-oxygen, positive-pressure environment inside the capsule, and the fact that the capsule door opened inward. Both of these design elements were scrapped in subsequent missions, and the second was replaced with an outward-opening hatch nominally to facilitate spacewalks. Lessons learned from Apollo 1 were also taken into account during the design of the Space Shuttle.

STS-51-L and STS-107 (the Challenger and Columbia accidents respectively) are two Space Shuttle (or Space Transportation System) launches known mostly for their accidents and subsequent losses of life. The Challenger disaster was attributed by the Rogers Commission (the investigative body set up after the accident) to poor performance of the solid rocket booster (SRB) O-rings. The O-rings lost integrity and became brittle at low temperatures, such as those present on the morning of the launch. The failure of the O-rings caused “blow-by,” where hot gasses escaped the booster joint, ultimately resulting in the destruction of Challenger. The Rogers Commission also cited both NASA and SRB contractor Morton Thiokol for a failure to redesign the SRB joint, known to be dangerous—manifestations of “go fever.”

According to the Columbia Accident Investigation Board, the disaster on STS-107 was due to a piece of foam from the external fuel tank hitting and breaching the left wing of the Orbiter during launch. The breach damaged the heat shielding, allowing hot gas to enter the Orbiter during re-entry. Ultimately, that damage caused the vehicle to disintegrate over Texas.

Both missions resulted in the complete loss of crew (seven crew were on each mission) and orbiters. Both modes of failure had been previously observed in earlier missions, but went un-fixed because those missions were successful.

The Apollo-Soyuz Test Project marked a definite end to the Space Race, and was a symbol of the de-escalation of tensions between the US and the USSR. Deke Slayton, an original Mercury 7 astronaut grounded for medical reasons until 1973, was accompanied by Tom Stafford and Vance Brand on the last launch of Apollo before the advent of the Space Shuttle. The mission demonstrated that two dissimilar spacecraft could rendezvous and dock while in space (an Apollo Command Module and Soyuz 19 docked), and also enabled the crew of Soyuz to photograph the Sun’s corona through an artificial eclipse created by the Apollo spacecraft. Each spacecraft also carried out independent experiments.

SpaceX CRS-1 (also called SpX-1 or CRS-1) was the first commercial mission to resupply the International Space Station (ISS). A structural failure in one of the nine Merlin engines that make up the Falcon 9 rocket first stage necessitated a longer burn with the remaining eight engines. That correction resulted in a proper orbital insertion for the primary payload (a Dragon resupply vehicle), but an unstable, decaying orbit for its secondary payload (an ORBCOMM satellite). This was taken as a proof of concept by SpaceX for the redundant, multiple-engine design. The craft successfully berthed with the ISS and successfully carried out its primary mission, re-supplying the space station and returning cargo to Earth.

SM1 corrected Hubble’s flawed optics by installing COSTAR (a corrective optics system), while removing the High-Speed Photometer to make room. It also replaced the original Wide Field and Planetary Camera, or WFPC “wiff-pick”, with WFPC2, which a camera that had optical correction built in.

SM3B replaced the Faint Object Camera (FOC) with the Advanced Camera for Surveys (ACS), and also repaired NICMOS, which was installed during SM2.

SM4 was originally cancelled after the Columbia Disaster by then-NASA Administrator Sean O’Keefe, but was revived by Michael Griffin, who took over the post in 2005. SM4 installed WFC3 (made from some parts of the original WFPC) and the Cosmic Origins Spectrograph (COS), and conducted other repairs. No further repairs are planned, as much of HST’s functionality will be replicated with the James Webb Space Telescope, scheduled for launch in 2018.